A security chip performs highly reliable encryption processing on data stored in the security chip, so that the data is hardly illegally stolen. An operating condition (Operating Condition) (such as, an electrical condition) in which the security chip operates needs to ensure that a circuit (such as a CPU circuit, an encryption and decryption circuit, and a random number generation circuit) in the security chip normally operates. Once a parameter of the electrical condition in which the security chip operates exceeds a withstanding threshold of a circuit in the security chip, an error may occur during operation of the circuit in the security chip. In this case, the data stored in the security chip may leak.
At present, various sensors (sensor) are integrated in the security chip, and are respectively used to monitor condition components (such as a voltage, a temperature, light, and clock information) of the operating condition in which the security chip operates. The sensors analyze the condition components by using a signal processing module, so as to determine whether the operating condition in which the security chip operates is proper. If the operating condition is improper, an alarm is generated. However, at present, monitoring on each of the foregoing condition components is separately performed within the security chip. For example, as shown in FIG. 1, a voltage sensor is used to monitor the voltage, a temperature sensor is used to monitor the temperature, an optical sensor is used to monitor an incident ray, and a frequency sensor is used to monitor the clock information. The various sensors act independent of each other, and all the sensors are mainly an analog circuit.
However, an area of the analog circuit cannot be significantly reduced as a process evolves. Therefore, a larger area of the analog circuit indicates easier identification of the analog circuit in a security chip layout, and an attack risk is relatively high.